Education provides the opportunity to face social change, and a teacher's role in this process is significant. Until recently, teacher expertise was defined only in terms of knowledge of the subject taught, and teaching itself was not considered a professional activity. This paper describes the entailment of a teacher's profession, examining the difference between professionalism and amateurism. After discussing the importance of integrity in teaching and the relationship of integrity to professionalism, the paper explains the need to have a strong knowledge base in order to move forward and improve. If teachers do not equip themselves with the necessary knowledge and attitudes about change, they will be left behind as change occurs. Teachers are the key to quality education and must be familiar with current educational technology (e.g., tele-access and virtual publishing). Knowledge can be categorized into two series of distinctions: (1) public knowledge, which is necessarily explicit, and personal knowledge, which can be explicit or tacit; and (2) and propositional knowledge, which is "knowing that"; procedural knowledge, which is "knowing how"; and images and impressions, which are held in memory but not represented in propositional form. There are four kinds of processes which contribute to professional performance: processes for acquiring and interpreting information, skilled behavior, deliberate processes, and meta processes. (SM)